/* System sans, large ink-like headings, and quiet reading text. */
html { font-size: 16px; }
body, button, select, textarea {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
}
body { font-size: 18px; line-height: 1.62; }
p, li, a, label, select, textarea, button { overflow-wrap: anywhere; }
button, select, textarea { font-size: 16px; line-height: 1.5; }
a { font-size: inherit; }
h1 { font-size: clamp(44px, 6.2vw, 90px); font-weight: 900; letter-spacing: -.055em; line-height: 1.02; max-width: 16ch; text-wrap: balance; }
.opening-page h1 { font-size: clamp(58px, 7.4vw, 106px); max-width: 14ch; letter-spacing: -.065em; text-transform: uppercase; line-height: .95; }
.opening-page h1 span { font-size: .57em; letter-spacing: -.035em; line-height: 1.04; max-width: 15ch; }
h2 { font-size: clamp(26px, 2.5vw, 35px); line-height: 1.16; letter-spacing: -.035em; font-weight: 800; max-width: 34ch; text-wrap: balance; }
h3 { font-size: 22px; line-height: 1.25; letter-spacing: -.018em; font-weight: 750; }
.notebook-name { font-size: 20px; font-weight: 850; letter-spacing: -.03em; }
.notebook-name span { font-weight: 400; padding-inline: .25em; }
.notebook-purpose, .breadcrumb, .page-label, .source-label, .notebook-footer, .worksheet-status { font-size: 16px; }
.page-label, .source-label { font-weight: 750; }
.page-label { line-height: 1.4; }
.source-label { letter-spacing: .025em; }
.cover-lead { font-size: 21px; line-height: 1.5; }
.entry-title { font-size: 23px; font-weight: 800; line-height: 1.2; letter-spacing: -.02em; }
.entry-description { font-size: 18px; line-height: 1.45; font-weight: 400; }
.entry-arrow { font-size: 28px; line-height: 1; }
.source-link { font-size: 16px; font-weight: 700; line-height: 1.4; text-decoration-thickness: 1.5px; text-underline-offset: .22em; }
.notebook-link, button { font-size: 16px; line-height: 1.5; font-weight: 750; text-align: left; }
label { font-size: 18px; line-height: 1.4; font-weight: 700; }
.notebook-entry, .notebook-link { text-decoration: none; }
@media (max-width: 760px) {
  .notebook-name { max-width: 14ch; }
  .notebook-purpose { line-height: 1.4; }
  .cover-lead { font-size: 19px; }
  .opening-page h1 { font-size: clamp(48px, 13.9vw, 74px); }
  .reading-page h1 { font-size: clamp(43px, 11.5vw, 65px); }
}
@media print {
  body { font-size: 16px; line-height: 1.5; }
  h1, .opening-page h1 { font-size: 44px; }
  h2 { font-size: 25px; }
  .cover-lead { font-size: 18px; }
}